CVE-2026-9084
📛 CVE Title
MISP OIDC authentication bypass via automatic email-based account linking under insecure IdP configurations
Description
MISP’s OIDC authentication plugin allowed automatic linking of an OIDC identity to an existing local user account based on the email claim when the local account had no stored sub value. Under insecure or untrusted IdP configurations where email ownership is not enforced, an attacker with a valid OIDC token could assert a victim’s email address and authenticate as that user, leading to account takeover.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- CIRCL
- CVSS severity
- MEDIUM
- CVSS score
- 6.0 / 10
- CVSS vector
CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N- Effective score
- 6.0 / 10 MEDIUM source: CNA overview
- CWE(s)
-
CWE-287 - Reserved
- 2026-05-20
- Published
- 2026-05-20 14:22 UTC
- Last updated
- 2026-05-20 15:28 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/9xxx/CVE-2026-9084.json
- Linked Threat
- CVE-2026-9084 — CVE-2026-9084
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-20 16:16:28 UTC
- NVD last modified
- 2026-05-20 17:31:45 UTC
- EPSS score
- 0.0003 (probability of exploitation in next 30 days)
- EPSS percentile
- 7.57% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD / KEV / EPSS data refreshed 2026-05-25 00:32 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-31123 - Assigner
- CIRCL
- Published
- May 20, 2026, 2:22:59 PM
- Updated
- May 20, 2026, 3:28:55 PM
- EUVD base score (CVSS 4.0)
-
6.0 / 10
CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N - EUVD-reported EPSS
- 0.0300
- Vendors
- MISP
- Products
-
MISP (2.5.0 ≤2.5.37)
- Aliases
-
GHSA-5895-8h7c-2833
ENISA description: MISP’s OIDC authentication plugin allowed automatic linking of an OIDC identity to an existing local user account based on the email claim when the local account had no stored sub value. Under insecure or untrusted IdP configurations where email ownership is not enforced, an attacker with a valid OIDC token could assert a victim’s email address and authenticate as that user, leading to account takeover.
EUVD references (1)
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| misp | misp |
2.5.0 (affected)
|
— |
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
Web references (4)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://github.com/MISP/MISP/commit/71f5662c1b5886613d2cd5c72fd93bb4ca6fa172 tenable:github.com
- https://nvd.nist.gov/vuln/detail/CVE-2026-9084 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-9084 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
NVD-tagged references (1)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://github.com/MISP/MISP/commit/71f5662c1b5886613d2cd5c72fd93bb4ca6fa172 5a6e4751-2f3f-4070-9419-94fb35b644e8
Remediations (17)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:app.opencve.io
MISP's OIDC authentication plugin allowed automatic linking of an OIDC identity to an existing local user account based on the email claim when the local account had no stored sub value. Under insecure or untrusted IdP configurations where email ownership is not enforced, an attacker with a valid OIDC token could assert a victim's email address and authenticate as that user, leading to ...
2026-05-23 22:18 UTC -
web:cve.enginsight.com
CVE-2026-9084 - MISP's OIDC authentication plugin allowed automatic linking of an OIDC identity to an existing local user account based on the email claim when the local …
2026-05-23 22:18 UTC -
web:cvefeed.io
The following products are affected by CVE-2026-9084 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.
2026-05-23 22:18 UTC -
web:cyberpress.org
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .
2026-05-23 22:18 UTC -
web:nvd.nist.gov
An official website of the United States government Here's how you know
2026-05-23 22:18 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-05-23 22:18 UTC -
web:vulmon.com
Vulnerability Summary MISP's OIDC authentication plugin allowed automatic linking of an OIDC identity to an existing local user account based on the email claim when the local account had no stored sub value. Under insecure or untrusted IdP configurations where email ownership is not enforced, an attacker with a valid OIDC token could assert a victim's email address and authenticate as ...
2026-05-23 22:18 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-05-23 22:18 UTC -
web:www.msn.com
Original story: Microsoft has released an emergency patch for a vulnerability in the company's Office programs that's already being exploited by hackers.
2026-05-23 22:18 UTC -
web:www.thehackerwire.com
CVE-2026-9084 is a Info severity security vulnerability. MISP's OIDC authentication plugin allowed automatic linking of an OIDC identity to an existing local user account based on the email claim when the local... How do I fix or mitigate CVE-2026-9084 ? When was CVE-2026-9084 disclosed? This vulnerability was publicly disclosed on May 20, 2026 .
2026-05-23 22:18 UTC -
web:cyberinsider.com
Microsoft has released its April 2026 Patch Tuesday updates for Windows 11 versions 24H2 and 25H2, to fix security bugs across the operating system. The security release addresses 165 flaws, including one actively exploited SharePoint spoofing flaw and multiple "more likely to be exploited" Windows bugs affecting core components.
2026-05-26 02:59 UTC -
web:threatprotect.qualys.com
With Qualys Policy Audit's out-of-the-box mitigation or Compensatory Controls, which reduce the risk of a vulnerability being exploited because the remediation ( fix / patch ) cannot be done immediately, these security controls are not recommended by any industry standards, such as CIS and DISA-STIG.
2026-05-26 02:59 UTC -
web:www.bleepingcomputer.com
Today is Microsoft's April 2026 Patch Tuesday with security updates for 167 flaws, including 2 zero-day vulnerabilities.
2026-05-26 02:59 UTC -
web:www.crowdstrike.com
Microsoft's April 2026 Patch Tuesday addresses 164 CVEs , featuring 8 Critical vulnerabilities, one exploited zero-day, and one disclosed zero-day.
2026-05-26 02:59 UTC -
web:www.lansweeper.com
Patch Tuesday Microsoft report by Lansweeper. get an overview from all the Microsoft Patch Tuesday 's and fix the vulnerabilities.
2026-05-26 02:59 UTC -
web:www.pcworld.com
This month's Patch Tuesday includes an actively exploited Office zero-day vulnerability and several critical RCE bugs in Windows and Remote Desktop.
2026-05-26 02:59 UTC -
web:www.windowslatest.com
Windows 11 April 2026 update adds Narrator Copilot support, faster Settings, File Explorer fixes, and key security improvements.
2026-05-26 02:59 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-9084.json.
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